Before this patch:
# ./perf test 39 41
39: LLVM search and compile :
39.1: Basic BPF llvm compile : Ok
39.2: kbuild searching : FAILED!
39.3: Compile source for BPF prologue generation : Skip
39.4: Compile source for BPF relocation : Skip
41: BPF filter :
41.1: Basic BPF filtering : Ok
41.2: BPF pinning : Ok
41.3: BPF prologue generation : FAILED!
41.4: BPF relocation checker : Skip
#
Using 'perf test -v' for these tests shows that it is not finding
uapi/linux/fs.h, which ends up being because we don't setup the right header
path. Fix it.
After this patch:
# perf test 39 41
39: LLVM search and compile :
39.1: Basic BPF llvm compile : Ok
39.2: kbuild searching : Ok
39.3: Compile source for BPF prologue generation : Ok
39.4: Compile source for BPF relocation : Ok
41: BPF filter :
41.1: Basic BPF filtering : Ok
41.2: BPF pinning : Ok
41.3: BPF prologue generation : Ok
41.4: BPF relocation checker : Ok
#
Longer description:
In llvm-utils.c we use some techniques to obtain the kbuild make
directives and that recently stopped working as now 'ar' gets called and
expects to find the dummy.o used to echo these variables:
$(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS)
Add the $(CC) line to satisfy that, making sure this works with all
kernels, i.e. preserving the temp directory and files in it used for
this technique we can see that it works everywhere:
# make -s -C /lib/modules/5.4.18-100.fc30.x86_64/build M=/tmp/tmp.qgaFHgxjZ4/ clean
# ls -la /tmp/tmp.qgaFHgxjZ4/
total 4
drwx------. 2 root root 80 Feb 14 09:42 .
drwxrwxrwt. 47 root root 1200 Feb 14 09:42 ..
-rw-r--r--. 1 root root 0 Feb 13 17:14 dummy.c
-rw-r--r--. 1 root root 121 Feb 13 17:14 Makefile
#
# cat /tmp/tmp.qgaFHgxjZ4/Makefile
obj-y := dummy.o
$(obj)/%.o: $(src)/%.c
@echo -n "$(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS)"
$(CC) -c -o $@ $<
#
Then build with an old kernel Makefile:
# make -s -C /lib/modules/5.4.18-100.fc30.x86_64/build M=/tmp/tmp.qgaFHgxjZ4/ dummy.o
-nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/9/include -I./arch/x86/include -I./arch/x86/include/generated -I./include -I./arch/x86/include/uapi -I./arch/x86/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h
#
# ls -la /tmp/tmp.qgaFHgxjZ4/
total 8
drwx------. 2 root root 100 Feb 14 09:43 .
drwxrwxrwt. 47 root root 1200 Feb 14 09:43 ..
-rw-r--r--. 1 root root 0 Feb 13 17:14 dummy.c
-rw-r--r--. 1 root root 936 Feb 14 09:43 dummy.o
-rw-r--r--. 1 root root 121 Feb 13 17:14 Makefile
#
And a new one:
# make -s -C /lib/modules/5.4.18-100.fc30.x86_64/build M=/tmp/tmp.qgaFHgxjZ4/ clean
# ls -la /tmp/tmp.qgaFHgxjZ4/
total 4
drwx------. 2 root root 80 Feb 14 09:43 .
drwxrwxrwt. 47 root root 1200 Feb 14 09:43 ..
-rw-r--r--. 1 root root 0 Feb 13 17:14 dummy.c
-rw-r--r--. 1 root root 121 Feb 13 17:14 Makefile
# make -s -C /lib/modules/5.6.0-rc1+/build M=/tmp/tmp.qgaFHgxjZ4/ dummy.o
-nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/9/include -I/home/acme/git/linux/arch/x86/include -I./arch/x86/include/generated -I/home/acme/git/linux/include -I./include -I/home/acme/git/linux/arch/x86/include/uapi -I./arch/x86/include/generated/uapi -I/home/acme/git/linux/include/uapi -I./include/generated/uapi -include /home/acme/git/linux/include/linux/kconfig.h
#
# ls -la /tmp/tmp.qgaFHgxjZ4/
total 16
drwx------. 2 root root 160 Feb 14 09:44 .
drwxrwxrwt. 47 root root 1200 Feb 14 09:44 ..
-rw-r--r--. 1 root root 158 Feb 14 09:44 built-in.a
-rw-r--r--. 1 root root 149 Feb 14 09:44 .built-in.a.cmd
-rw-r--r--. 1 root root 0 Feb 13 17:14 dummy.c
-rw-r--r--. 1 root root 936 Feb 14 09:44 dummy.o
-rw-r--r--. 1 root root 121 Feb 13 17:14 Makefile
-rw-r--r--. 1 root root 0 Feb 14 09:44 modules.order
#
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: https://www.spinics.net/lists/linux-perf-users/msg10600.html
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
For data collected on machines with front end stalled cycles supported,
such as found on modern AMD CPU families, commit 146540fb54 ("perf
stat: Always separate stalled cycles per insn") introduces a new line in
CSV output with a leading comma that upsets some automated scripts.
Scripts have to use "-e ex_ret_instr" to work around this issue, after
upgrading to a version of perf with that commit.
We could add "if (have_frontend_stalled && !config->csv_sep)" to the not
(total && avg) else clause, to emphasize that CSV users are usually
scripts, and are written to do only what is needed, i.e., they wouldn't
typically invoke "perf stat" without specifying an explicit event list.
But - let alone CSV output - why should users now tolerate a constant
0-reporting extra line in regular terminal output?:
BEFORE:
$ sudo perf stat --all-cpus -einstructions,cycles -- sleep 1
Performance counter stats for 'system wide':
181,110,981 instructions # 0.58 insn per cycle
# 0.00 stalled cycles per insn
309,876,469 cycles
1.002202582 seconds time elapsed
The user would not like to see the now permanent:
"0.00 stalled cycles per insn"
line fixture, as it gives no useful information.
So this patch removes the printing of the zeroed stalled cycles line
altogether, almost reverting the very original commit fb4605ba47
("perf stat: Check for frontend stalled for metrics"), which seems like
it was written to normalize --metric-only column output of common Intel
machines at the time: modern Intel machines have ceased to support the
genericised frontend stalled metrics AFAICT.
AFTER:
$ sudo perf stat --all-cpus -einstructions,cycles -- sleep 1
Performance counter stats for 'system wide':
244,071,432 instructions # 0.69 insn per cycle
355,353,490 cycles
1.001862516 seconds time elapsed
Output behaviour when stalled cycles is indeed measured is not affected
(BEFORE == AFTER):
$ sudo perf stat --all-cpus -einstructions,cycles,stalled-cycles-frontend -- sleep 1
Performance counter stats for 'system wide':
247,227,799 instructions # 0.63 insn per cycle
# 0.26 stalled cycles per insn
394,745,636 cycles
63,194,485 stalled-cycles-frontend # 16.01% frontend cycles idle
1.002079770 seconds time elapsed
Fixes: 146540fb54 ("perf stat: Always separate stalled cycles per insn")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200207230613.26709-1-kim.phillips@amd.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
`tools/perf/util/map.c` has a function named `maps__insert` that
acquires a write lock if its in multithread context.
Even though this lock is released when function successfully completes,
there's a branch that is executed when `maps_by_name == NULL` that
returns from this function without releasing the write lock.
Added an `up_write` to release the lock when this happens.
Fixes: a7c2b572e2 ("perf map_groups: Auto sort maps by name, if needed")
Signed-off-by: Cengiz Can <cengiz@kernel.wtf>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200120141553.23934-1-cengiz@kernel.wtf
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Kernel commit 88903c4643 ("tracing/probe: Add ustring type for user-space string")
adds support for user-space strings when type 'ustring' is specified.
Here is an example using sysfs command line interface
for kprobes:
Function to probe:
struct filename *
getname_flags(const char __user *filename, int flags, int *empty)
Setup:
# cd /sys/kernel/debug/tracing/
# echo 'p:tmr1 getname_flags +0(%r2):ustring' > kprobe_events
# cat events/kprobes/tmr1/format | fgrep print
print fmt: "(%lx) arg1=\"%s\"", REC->__probe_ip, REC->arg1
# echo 1 > events/kprobes/tmr1/enable
# touch /tmp/111
# echo 0 > events/kprobes/tmr1/enable
# cat trace|fgrep /tmp/111
touch-5846 [005] d..2 255520.717960: tmr1:\
(getname_flags+0x0/0x400) arg1="/tmp/111"
Doing the same with the perf tool fails.
Using type 'string' succeeds:
# perf probe "vfs_getname=getname_flags:72 pathname=filename:string"
Added new event:
probe:vfs_getname (on getname_flags:72 with pathname=filename:string)
....
# perf probe -d probe:vfs_getname
Removed event: probe:vfs_getname
However using type 'ustring' fails (output before):
# perf probe "vfs_getname=getname_flags:72 pathname=filename:ustring"
Failed to write event: Invalid argument
Error: Failed to add events.
#
Fix this by adding type 'ustring' in function
convert_variable_type().
Using ustring succeeds (output after):
# ./perf probe "vfs_getname=getname_flags:72 pathname=filename:ustring"
Added new event:
probe:vfs_getname (on getname_flags:72 with pathname=filename:ustring)
You can now use it in all perf tools, such as:
perf record -e probe:vfs_getname -aR sleep 1
#
Note: This issue also exists on x86, it is not s390 specific.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: sumanthk@linux.ibm.com
Link: http://lore.kernel.org/lkml/20200120132011.64698-2-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf with CoreSight fails to record trace data with command:
perf record -e cs_etm/@tmc_etr0/u --per-thread ls
failed to set sink "" on event cs_etm/@tmc_etr0/u with 21 (Is a
directory)/perf/
This failure is root caused with the commit 1dc925568f ("perf
parse: Add a deep delete for parse event terms").
The log shows, cs_etm fails to parse the sink attribution; cs_etm event
relies on the event configuration to pass sink name, but the event
specific configuration data cannot be passed properly with flow:
get_config_terms()
ADD_CONFIG_TERM(DRV_CFG, term->val.str);
__t->val.str = term->val.str;
`> __t->val.str is assigned to term->val.str;
parse_events_terms__purge()
parse_events_term__delete()
zfree(&term->val.str);
`> term->val.str is freed and assigned to NULL pointer;
cs_etm_set_sink_attr()
sink = __t->val.str;
`> sink string has been freed.
To fix this issue, in the function get_config_terms(), this patch
changes to use strdup() for allocation a new duplicate string rather
than directly assignment string pointer.
This patch addes a new field 'free_str' in the data structure
perf_evsel_config_term; 'free_str' is set to true when the union is used
as a string pointer; thus it can tell perf_evsel__free_config_terms() to
free the string.
Fixes: 1dc925568f ("perf parse: Add a deep delete for parse event terms")
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lore.kernel.org/lkml/20200117055251.24058-2-leo.yan@linaro.org
[ Use zfree() in perf_evsel__free_config_terms ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
:# modified: tools/perf/util/evsel_config.h
Using .st_ctime clobbers the timestamp information in perf report header
whenever any operation is done with the file. Even tar-ing and untar-ing
the perf.data file (which preserves the file last modification timestamp)
doesn't prevent that:
[Michael@Diego tmp]$ ls -l perf.data
-> -rw-------. 1 Michael Michael 169888 Dec 2 15:23 perf.data
[Michael@Diego tmp]$ perf report --header-only
# ========
-> # captured on : Mon Dec 2 15:23:42 2019
[...]
[Michael@Diego tmp]$ tar c perf.data | xz > perf.data.tar.xz
[Michael@Diego tmp]$ mkdir aaa
[Michael@Diego tmp]$ cd aaa
[Michael@Diego aaa]$ xzcat ../perf.data.tar.xz | tar x
[Michael@Diego aaa]$ ls -l -a
total 172
drwxrwxr-x. 2 Michael Michael 23 Jan 14 11:26 .
drwxrwxr-x. 6 Michael Michael 4096 Jan 14 11:26 ..
-> -rw-------. 1 Michael Michael 169888 Dec 2 15:23 perf.data
[Michael@Diego aaa]$ perf report --header-only
# ========
-> # captured on : Tue Jan 14 11:26:16 2020
[...]
When using .st_mtime instead, correct information is printed:
[Michael@Diego aaa]$ ~/acme/tools/perf/perf report --header-only
# ========
-> # captured on : Mon Dec 2 15:23:42 2019
[...]
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
LPU-Reference: 20200114104236.31555-1-mpetlan@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The objdump utility has useful --prefix / --prefix-strip options to
allow changing source code file names hardcoded into executables' debug
info. Add options to 'perf report', 'perf top' and 'perf annotate',
which are then passed to objdump.
$ mkdir foo
$ echo 'main() { for (;;); }' > foo/foo.c
$ gcc -g foo/foo.c
foo/foo.c:1:1: warning: return type defaults to ‘int’ [-Wimplicit-int]
1 | main() { for (;;); }
| ^~~~
$ perf record ./a.out
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.230 MB perf.data (5721 samples) ]
$ mv foo bar
$ perf annotate
<does not show source code>
$ perf annotate --prefix=/home/ak/lsrc/git/bar --prefix-strip=5
<does show source code>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
LPU-Reference: 20200107210444.214071-1-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Use struct mmap_cpu_mask type for the tool's thread and mmap data
buffers to overcome current 1024 CPUs mask size limitation of cpu_set_t
type.
Currently glibc's cpu_set_t type has an internal mask size limit of 1024
CPUs.
Moving to the 'struct mmap_cpu_mask' type allows overcoming that limit.
The tools bitmap API is used to manipulate objects of 'struct mmap_cpu_mask'
type.
Committer notes:
To print the 'nbits' struct member we must use %zd, since it is a
size_t, this fixes the build in some toolchains/arches.
Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/96d7e2ff-ce8b-c1e0-d52c-aa59ea96f0ea@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When a map is create to represent the main kernel area (vmlinux) with
map__new2() we allocate an extra area to store a pointer to the 'struct
maps' for the kernel maps, so that we can access that struct when
loading ELF files or kallsyms, as we will need to split it in multiple
maps, one per kernel module or ELF section (such as ".init.text").
So when map->dso->kernel is non-zero, it is expected that
map__kmap(map)->kmaps to be set to the tree of kernel maps (modules,
chunks of the main kernel, bpf progs put in place via
PERF_RECORD_KSYMBOL, the main kernel).
This was not the case when we were splitting the main kernel into chunks
for its ELF sections, which ended up making 'perf report --children'
processing a perf.data file with callchains to trip on
__map__is_kernel(), when we press ENTER to see the popup menu for main
histogram entries that starts at a symbol in the ".init.text" ELF
section, e.g.:
- 8.83% 0.00% swapper [kernel.vmlinux].init.text [k] start_kernel
start_kernel
cpu_startup_entry
do_idle
cpuidle_enter
cpuidle_enter_state
intel_idle
Fix it.
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/20191218190120.GB13282@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Before this patch, perf expected that there might be NPROC*4 unique
cache entries at max, however, it also expected that some of them would
be shared and/or of the same size, thus the final number of entries
would be reduced to be lower than NPROC*4. In case the number of entries
hadn't been reduced (was NPROC*4), the warning was printed.
However, some systems might have unusual cache topology, such as the
following two-processor KVM guest:
cpu level shared_cpu_list size
0 1 0 32K
0 1 0 64K
0 2 0 512K
0 3 0 8192K
1 1 1 32K
1 1 1 64K
1 2 1 512K
1 3 1 8192K
This KVM guest has 8 (NPROC*4) unique cache entries, which used to make
perf printing the message, although there actually aren't "way too many
cpu caches".
v2: Removing unused argument.
v3: Unifying the way we obtain number of cpus.
v4: Removed '& UINT_MAX' construct which is redundant.
Signed-off-by: Michael Petlan <mpetlan@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
LPU-Reference: 20191208162056.20772-1-mpetlan@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit f01642e491 ("perf metricgroup: Support multiple events for
metricgroup") introduced support for multiple events in a metric group.
But with the current upstream, metric events names are not printed
properly
In power9 platform:
command:# ./perf stat --metric-only -M translation -C 0 -I 1000 sleep 2
1.000208486
2.000368863
2.001400558
Similarly in skylake platform:
command:./perf stat --metric-only -M Power -I 1000
1.000579994
2.002189493
With current upstream version, issue is with event name comparison logic
in find_evsel_group(). Current logic is to compare events belonging to a
metric group to the events in perf_evlist. Since the break statement is
missing in the loop used for comparison between metric group and
perf_evlist events, the loop continues to execute even after getting a
pattern match, and end up in discarding the matches.
Incase of single metric event belongs to metric group, its working fine,
because in case of single event once it compare all events it reaches to
end of perf_evlist.
Example for single metric event in power9 platform:
command:# ./perf stat --metric-only -M branches_per_inst -I 1000 sleep 1
1.000094653 0.2
1.001337059 0.0
This patch fixes the issue by making sure once we found all events
belongs to that metric event matched in find_evsel_group(), we
successfully break from that loop by adding corresponding condition.
With this patch:
In power9 platform:
command:# ./perf stat --metric-only -M translation -C 0 -I 1000 sleep 2
result:#
time derat_4k_miss_rate_percent derat_4k_miss_ratio derat_miss_ratio derat_64k_miss_rate_percent derat_64k_miss_ratio dslb_miss_rate_percent islb_miss_rate_percent
1.000135672 0.0 0.3 1.0 0.0 0.2 0.0 0.0
2.000380617 0.0 0.0 0.0 0.0 0.0 0.0 0.0
command:# ./perf stat --metric-only -M Power -I 1000
Similarly in skylake platform:
result:#
time Turbo_Utilization C3_Core_Residency C6_Core_Residency C7_Core_Residency C2_Pkg_Residency C3_Pkg_Residency C6_Pkg_Residency C7_Pkg_Residency
1.000563580 0.3 0.0 2.6 44.2 21.9 0.0 0.0 0.0
2.002235027 0.4 0.0 2.7 43.0 20.7 0.0 0.0 0.0
Committer testing:
Before:
[root@seventh ~]# perf stat --metric-only -M Power -I 1000
# time
1.000383223
2.001168182
3.001968545
4.002741200
5.003442022
^C 5.777687244
[root@seventh ~]#
After the patch:
[root@seventh ~]# perf stat --metric-only -M Power -I 1000
# time Turbo_Utilization C3_Core_Residency C6_Core_Residency C7_Core_Residency C2_Pkg_Residency C3_Pkg_Residency C6_Pkg_Residency C7_Pkg_Residency
1.000406577 0.4 0.1 1.4 97.0 0.0 0.0 0.0 0.0
2.001481572 0.3 0.0 0.6 97.9 0.0 0.0 0.0 0.0
3.002332585 0.2 0.0 1.0 97.5 0.0 0.0 0.0 0.0
4.003196624 0.2 0.0 0.3 98.6 0.0 0.0 0.0 0.0
5.004063851 0.3 0.0 0.7 97.7 0.0 0.0 0.0 0.0
^C 5.471260276 0.2 0.0 0.5 49.3 0.0 0.0 0.0 0.0
[root@seventh ~]#
[root@seventh ~]# dmesg | grep -i skylake
[ 0.187807] Performance Events: PEBS fmt3+, Skylake events, 32-deep LBR, full-width counters, Intel PMU driver.
[root@seventh ~]#
Fixes: f01642e491 ("perf metricgroup: Support multiple events for metricgroup")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20191120084059.24458-1-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>